The present invention concerns an absorbent product such as a sanitary napkin, a diaper, an incontinence pad or a similar item, comprising an absorbent body enclosed between a first liquid-permeable covering layer and a second liquid-impermeable covering layer whereby the absorbent body comprises an absorbent layer having a first and a second surface, and that a first material layer is arranged in contact with the absorbent layer""s first surface and that a second material layer is arranged in contact with the absorbent layer""s second surface.
Lately absorbent products such as sanitary napkins, diapers, incontinence pads or similar items have come to be made thinner and more flexible, while concurrently their component materials have been improved and achieved higher absorbent capacities. Thus products have become both more comfortable and more discrete to wear while their effectiveness has been maintained. Another important advantage is that the products can be packed into less bulky packages whereby storage and transport is appreciably less expensive.
To be able to fully exploit the advantages of the new thinner products, it is however desirable that they have a shape such that no empty, unused regions are formed between products when in a package. Furthermore it is also desirable that before the products are packaged they can be folded together, without loss of shape or function, into a shape which is more manageable for the user. From a packaging point of view, such products should be essentially flat and preferably have a rectangular shape.
These requirements, however, correspond badly with the requirements which are placed on the product during use. To achieve a high user comfort and resistance to leakage, the product must in use, take up a three-dimensional form which adopts the user""s body shape without chafing or otherwise irritating the user""s skin.
Attempts which have been made up to now to solve this problem are most often built upon the use of special shaping elements made of plastic, or a similar material, which are put in the absorbent body. These shaping elements are activated when the product is used through being subjected to pressure from the user""s body, for example by compression between the user""s legs. Such shaping elements are described in EP 335,252 and EP 335,253.
The disadvantages with these known shaping elements are many. They are comparatively expensive and complicated to manufacture, which together with the increased material consumption makes the production of the finished product more expensive. With so called disposable products, that is products which are supposed to be discarded after only one use, manufacturing costs and material consumption are both extremely important factors to which considerable attention must be paid both in order that the product can be sold for a reasonable price and also that the quantity of material which has to be transported, stored and finally thrown away should be able to be minimized. Especially from an environmental view point it is desirable to minimize the quantity of material used.
Another disadvantage is that products containing special shaping elements cannot be packed folded together without the shaping elements being damaged or destroyed. Furthermore, shaping elements bring the risk that sharp folds or corners on the shaping element chafe and irritate the user""s skin.
A further method for bringing about the shaping of an absorbent product in use is through providing the product with fold indications in the form of welds or compression lines. The foremost disadvantage with this is that it is impossible to control that the desired bending or folding actually takes place in the intended direction. The risk that the product instead folds or bends in the opposite direction is considerable and thus, the leakage resistance of the product is strongly reduced. A further disadvantage is that welds or compression lines are stiff and hard which means that the risk of chafing and irritation of the user""s skin is considerable. In particular if the product has been folded together before use there is a big risk that sharp corners or folds have been formed wherever the folding together took place in the direction crossing the fold lines.
With the present invention however an absorbent product of the type described above in the introduction is achieved wherein the product set asides problems connected with earlier known such products.
A product formed according to the invention is distinguished principally in that at least one bend indication in the form of a through slit or elongated opening is arranged in the absorbent layer, and in that one of the absorbent layer""s surfaces is joined directly to the material layer lying in contact with this surface, within a region which most immediately surrounds the said bend indication and on each side of it and extends straight across and along essentially an entire length of the at least one bend indication, as well as the absorbent layer""s other surface within the said region is not directly joined to the material layer lying in contact with it, whereby bending of the parts of the product which are situated on each side of the bend indication is forced to take place in the direction away from the unjoined surface of the absorbent layer when the product is subjected to compressive forces which are principally directed perpendicular to the bend indication.
Further embodiments and characteristic features will become clear from the subsequent patent claims.
Through arranging in an absorbent layer a slit or elongated opening which extends through the thickness of the layer and the edge parts of which on one side of the absorbent layer are joined to a further material layer which is adjacent to the absorbent layer, while the edge parts of the slit on the opposite surface of the absorbent layer are movable in relation to one another in a direction principally perpendicular to the slit or opening, the bending and shaping of the absorbent body when it is being used can be directed and controlled as desired.
During the use of a product with such an absorbent body the slits interact with the compressive forces which the absorbent body is affected by when it placed inside a pair of underpants. In this connection the product is subjected to compression between the underpants and the user""s body and also to compressive forces from the user""s thighs acting principally perpendicular thereto. By the appropriate shaping and positioning of one or more slits or elongated openings, it is possible to cause the absorbent body to shape itself to the user""s body during use in such a manner that the risk of leakage of body fluids is minimized while at the same time both user comfort and discretion considerably increase.
In order to function as a distinct, well-defined bend indication, it is important that the elongated opening is not too wide. The opening is therefore most appropriately formed as a slit or as a narrow, slot-shaped hole in the absorbent layer. The width of the elongated opening should therefore not be more than 5 mm. In extremely thick absorbent layers (0.5 cm or thicker) it can, however, be necessary to provide openings with a width up to 1.5 cm.
The improved three-dimensional shaping can be brought about surprisingly enough without any cost increasing and stiffening shaping elements. It furthermore avoids the use of stiffening, difficult to bend and chafing welds, compressions or the like.
One embodiment of the absorbent product of the present invention comprises an absorbent body enclosed between a first liquid permeable covering layer and a second liquid impermeable covering layer, the absorbent body including at least one absorbent layer having opposing surfaces including a first surface and a second surface. A first material layer is arranged in contact with the first surface of the absorbent layer and a second material layer is arranged in contact with the second surface of the absorbent layer. At least one elongated bend indication opening is arranged in the at least one absorbent layer, wherein one of the first and second surfaces of the absorbent layer is joined directly with the one of said material layers in contact with said one of said surfaces of the absorbent layer within a region immediately surrounding the at least one elongated opening and extending straight across and along essentially an entire length of the at least one elongated opening on each side thereof. The other of said first and second surfaces of the absorbent layer is not directly joined to the one of said material layers in contact with said other of said first and second surfaces of the absorbent layer within said region such that, when the product is subjected to compressive forces directed primarily perpendicular to the elongated opening, bending is forced to take place in a direction away from said other of said first and second surfaces of the absorbent layer. The at least one elongated bend indication opening defines opposing wall surfaces separated by a predetermined distance, wherein the wall surfaces of the at least one elongated bend indication opening form a bend by separating a first distance at said one of said first and second surfaces and by a second distance at the other of said first and second surfaces, the second distance being greater than the first distance. Further, during bending, the first distance remains substantially the same as the predetermined distance at said one of said first and second surfaces.
A further embodiment of the absorbent product of the present invention comprises an absorbent body enclosed between a first liquid-permeable covering layer and a second liquid-impermeable covering layer, the absorbent body including at least one absorbent layer presenting a first surface and an opposite second surface. A first material layer is arranged in contact with the first surface of the absorbent layer and a second material layer is arranged in contact with the second surface of the absorbent layer. At least one bend indication in the form of a through slit is arranged in said absorbent layer. One of said first and second surfaces of the absorbent layer is joined directly with the layer in contact with said one surface of said first and second surfaces, within a region immediately surrounding said bend indication, on each side thereof and extending straight across and along essentially an entire length of the at least one bend indication, and the other of said first and second surfaces of the absorbent layer is not directly joined to the layer contacting said other of said first and second surfaces in said region. Thus, bending of parts of the product which lay on each side of the bend indication, when the product is subjected to compressive forces directed chiefly perpendicular to the bend indication, is forced to take place in a direction away from the other of said first and second surfaces of the absorbent layer which is not joined to the layer contacting said other of said first and second surfaces. Further, the absorbent layer has a thickness of 0.5 cm or greater and said through slit has a width up to 1.5 cm.
A still further embodiment of the absorbent product of the present invention comprises an absorbent body enclosed between a first liquid-permeable covering layer and a second liquid-impermeable covering layer, the absorbent body including at least one absorbent layer presenting a first surface and an opposite second surface. A first material layer is arranged in contact with the first surface of the absorbent layer and a second material layer is arranged in contact with the second surface of the absorbent layer. At least one bend indication in the form of a through slit is arranged in said absorbent layer, one of said first and second surfaces of the absorbent layer is joined directly with the layer in contact with said one surface of said first and second surfaces, within a region immediately surrounding said bend indication, on each side thereof and extending straight across and along essentially an entire length of the at least one bend indication, and the other of said first and second surfaces of the absorbent layer is not directly joined to the layer contacting said other of said first and second surfaces in said region. Thus, bending of parts of the product which lay on each side of the bend indication, when the product is subjected to compressive forces directed chiefly perpendicular to the bend indication, is forced to take place in a direction away from the other of said first and second surfaces of the absorbent layer which is not joined to the layer contacting said other of said first and second surfaces. The material layer is joined to the absorbent layer within said region so as to thereby maintain the through slit in position, and wherein a portion of said material layer bridges the through slit and acts as a hinge around which the absorbent layer bends.